Despite the hysterical reactions from some quarters of the right (“A victory for terrorists!”; “Can’t Try Them, So Fry Them!”; “Instrument of Surrender Signed by SCOTUS”), the Hamdan opinion was actually quite modest in scope. As Mark Tushnet explains:
And now to the final point: What would the legal position be were Congress to authorize exactly the same tribunals and Hamdan to be charged with a war crime before such a tribunal? It seems to me that the Hamdan opinion does not show, in any way, that such tribunals, authorized by Congress, would be impermissible. The only question the Court discusses is a separation-of-powers question, about the President’s power to convene these tribunals given the other processes Congress has authorized.
(2) What about the Geneva Convention and Common Article Three? First, as I read the opinion, the Court holds that Common Article Three requires trial before a regularly constituted tribunal, and interprets the term “regularly constituted” to mean, “constituted pursuant to the ordinary methods of establishing tribunals.” And, again as I read the opinion, a statute enacted by Congress creating these tribunals would satisfy that requirement. But, second, and even more obvious, Common Article Three is a provision in a treaty, and well-established law in the United States holds that subsequently enacted statutes can override preexisting treaty requirements (the last-in-time rule). So, even if the tribunals the President constituted violate Common Article Three, a congressional statute explicitly reconstituting them would not be unlawful as a matter of U.S. law.
Far from being overreach, if anything the case doesn’t go far enough; it is true that the case may have the effect of “sanitizing a vicious policy.” Nonetheless, this is not to say that the decision isn’t important. The tradition of the courts deferring to the political branches during times of conflict, while it clearly has gone too far in some cases, exists for sound reasons. I think, for example, that Lincoln was within his powers to initiate a blockade in 1861, and the Supreme Court was right to uphold his actions. Military conflicts do require some leeway for executive action.
However, there are two key distinctions here: 1)Lincoln (unlike Bush) was not acting against Congressional statutes, and 2)Lincoln never claimed that his Article II powers were unreguable. As Lederman and Balkin point out, the most important aspect of the decision is that it forces Congress to actually exercise its proper constitutional functions. The Court did not attempt to usurp the roles of the other branches, but simply Perhaps the conflict with Al Qaeda does require a different set of procedures than Congress has previously established. But if that’s true, it’s up to the administration to make the case to Congress and the public, and to get the law changed, rather than to simply exercise arbitrary power and ignore existing statutes. Hopefully Congress will create better procedures than the administration tried to use, but even legislative ratification of the bad procedures would be better in the long run than the Court simply ratifying lawless executive power, particularly in the case of a conflict that is essentially unbounded by time. Bad laws can be changed; the idea that the President is above the law is much, much worse.